Prevalence of potential candidates for electric-acoustic stimulation implant in a hearing-impaired population.

OBJECTIVE: To estimate the prevalence of potential electric-acoustic stimulation (EAS) implant candidates in a hearing-impaired population through a review of auditory examinations. METHODS: In total, 7356 patients underwent audiometric examination in our department between 2011 and 2014. The prevalence of patients meeting the audiometric criteria for EAS and standard cochlear implant (CI) was assessed. RESULTS: The percentage of EAS implant candidates meeting the pure-tone audiometric criteria was 0.71% (n=34) among the hearing-impaired individuals (n=4758) examined in our department, whereas 2.52% (n=120) met the criteria for standard CI. Among the 34 EAS implant candidates, 2 individuals (5.83%) received EAS implant surgery after approval of the EAS device in Japan. CONCLUSIONS: There was a lower prevalence of EAS implant candidates than standard CI candidates. Nevertheless, healthcare professionals should carefully examine the audiograms of patients with high frequency hearing loss with regard to meeting the indication criteria for EAS implant. This will enable patients to gain access to adequate information relating to further examinations and treatment options.

Acute retinal necrosis in a patient with remote severe herpes simplex encephalitis.

A 60-year-old man with a history of severe herpes simplex virus type 1 (HSV-1) encephalitis 2 years prior presented with acute onset of visual loss in the left eye. Dilated funduscopic examination showed retinitis and occlusive vasculitis with retinal necrosis. PCR of the vitreous fluid was positive for HSV-1, and he was diagnosed with acute retinal necrosis (ARN) due to HSV-1. The patient was treated with intravenous acyclovir and intravitreous foscarnet for 2 weeks, followed by high dose oral valacyclovir for 2 weeks. He was subsequently placed on planned life-long suppressive valacyclovir. His case demonstrates that acute visual loss concomitant with or subsequent to HSV-1 encephalitis warrants suspicion of ARN. Prompt therapy with effective antiviral medication is necessary to reduce the risk of sight-threatening complications. Chronic suppression with oral antiviral therapy after ARN is recommended to prevent involvement of the contralateral eye, though there is no consensus on the duration and dosage of antivirals.

Beneficial effects of preemptive kidney transplantation on calcium and phosphorus disorders in early post-transplant recipients.

BACKGROUND: Recently, preemptive kidney transplantation (PKT) has increased in Japan; however, the effects of PKT on calcium (Ca) and phosphorus (Pi) metabolism are poorly understood. METHODS: Thirty-two consecutive patients were enrolled in this study at Nagoya Daini Red Cross Hospital. Fifteen patients were in the PKT group and 17 patients were in the non-PKT group. Parameters of Ca and Pi metabolism, including fibroblast growth factor (FGF) 23 and intact parathyroid hormone, were measured before transplantation and 1, 3, and 24 weeks after transplantation. RESULTS: FGF 23 decreased dramatically in both groups after transplantation; however, FGF 23 before transplantation and at 1 and 3 weeks after transplantation was significantly lower in the PKT group than in the non-PKT group (p < 0.05). Although iPTH levels were higher in the PKT group than in the non-PKT group before transplantation, these levels were lower in the PKT group at 24 weeks after transplantation (p < 0.05). Corrected Ca was lower at 24 weeks in the PKT group (p < 0.05), whereas Pi was lower in the non-PKT group at 1 and 3 weeks (p < 0.05), but not significantly different at 24 weeks. Multivariate linear regression analysis revealed that FGF 23 before transplantation was the strongest predictor of Ca and Pi disorders in early post-transplant recipients. CONCLUSIONS: This study suggests that PKT has beneficial effects on Ca and Pi metabolism and pre-transplant FGF 23 levels are a good marker of post-transplant Ca and Pi metabolism disorders.

Comparative analysis of drug action on B-cell proliferation and differentiation for mycophenolic acid, everolimus, and prednisolone.

BACKGROUND: Although more attention has been paid recently to B-cell immunity, assay for B-cell analysis has yet to be clinically applicable because, unlike T cell, a B-cell culture system has not been well established. METHODS: We attempted to develop an in vitro culture system for the proliferation and differentiation of peripheral B cells into plasma cells, and to analyze the action of everolimus (EVR), mycophenolic acid (MPA), and prednisolone (PRD). RESULTS: Using a three-step culture system, peripheral CD19 B cells could differentiate into plasma cells and produce IgG antibody. Activated B cells (CD19(hi)CD38(lo)IgD(-)), plasmablasts (CD19(hi)CD38(hi)IgD(-)), and plasma cells (CD19(lo/-)CD38(hi)IgD(-)) were observed as a main cell subset in step 1 (day 0-4), 2 (day 4-7), and 3 (day 7-10), respectively. IgG production on day 10 was significantly suppressed by EVR, MPA, and PRD, but not cyclosporine. Although both EVR and MPA inhibited B-cell proliferation and differentiation in step 1, EVR suppressed B-cell differentiation in step 2. Only a high concentration of PRD significantly inhibited B-cell proliferation, differentiation, and IgG production in step 3. CONCLUSIONS: Although both MPA and EVR efficiently suppressed cell proliferation during the early phase of B-cell immune reaction, EVR could act in a later phase than MPA. PRD at a high concentration worked even in the last phase. An in vitro B-cell culture system would clarify the mode of drug action during B-cell differentiation and provide useful information on the effective selection or combination of immunosuppressive agents.

Magnetic force-assisted meniscal resection under arthroscopy.

Arthroscopic meniscectomy has become a standard procedure for a complete discoid meniscus or for displacement of a meniscal bucket handle tear, although it is not always easy due to poor visualization of the cutting portion. The purpose of this study is to examine whether meniscal resection can be easily carried out in a swine model using the magnetic force-assisted procedure, whereby a metal clip is attached to the meniscal flap and moved by an external magnetic force. Four fresh-frozen porcine lower extremities were used (age range: about 6 months). After opening the knee joint, a flap tear in the medial and lateral menisci was created. Then a metal clip was attached to the edge of the tear. With 20 cm distance between the knee and the disk of the external magnetic device, the flap was observed under arthroscopy. At the highest magnitude of 0.6 T, the direction of the magnetic field was changed. As the direction of the magnetic field was changed to move laterally, medially, up, and down, so the edge of the meniscal flap was observed to move in corresponding directions. Thanks to now having a clear view of the cutting portion, it was evident that meniscal resection could be easily carried out. Although we need to develop special instruments such as Titanium scissors and forceps and an external magnet system for surgery, the current study may be the first step towards a new era in the field of magnet-assisted arthroscopy.